So the services are pretty uniform. $200ish on a once a month gig will probably only get you about two hours of cleaning by two people, maybe only an hour and half.. I did a lot of calling around previously and the rate from the services initially is pretty consistent. And unfortunately, most of them don't really seem interested in a once a month gig and all of them want to play the 'initial' cleaning BS.
Previously we've used Molly Maids, You've got Maids, and some others. Saw the Tidy flyers but they seemed even more expensive than the other services.
Now we just cherry pick offers via email from services we've used before when they've got open spots that correspond to our availability.
Alternatively, you could fish on care.com for a housecleaner looking for a side hussle.